Hepatitis B reactivation risk and physician awareness in rheumatological patients receiving anti-tumor necrosis factor-α treatment

SUMMARY OBJECTIVE: We aimed to evaluate the risk of hepatitis B virus reactivation in rheumatic patients using anti-tumor necrosis factor-alpha drugs and the awareness of physicians about hepatitis B virus reactivation. METHODS: Demographic characteristics, pre- and post-treatment hepatitis markers, and laboratory parameters of patients receiving anti-tumor necrosis factor-alpha therapy in our rheumatology clinic were retrospectively examined. RESULTS: A total of 448 patients, 240 (53.6%) female and 208 (46.4%) male, were evaluated. Their mean age was 48.02±14.64 years. While HBsAg was examined in 443 (98.9%) patients before treatment, 7 (1.6%) patients were found to be HBsAg positive. While anti-HBc IgG was examined in 405 (90.4%) patients, it was positive in 69 (17%) patients. HBs Ag (total 446–99.6%) test was performed in three patients who were not tested for HBsAg before the treatment, and anti-HBc total (431–96.2% total) test was performed in 26 patients who were not tested for anti-HBc total. All HBsAg positive patients and 17 (24.6%) of those with previous hepatitis B received antiviral treatment. While the median follow-up period of the patients was 24 (6–60) months, no patient developed hepatitis B virus reactivation. CONCLUSION: The screening rates and awareness of physicians providing anti-tumor necrosis factor-alpha therapy for hepatitis B virus infection were found to be higher compared to similar studies. Hepatitis B virus reactivation did not develop in any patient. Since the risk of hepatitis B virus reactivation is low, especially in patients with previous hepatitis B, it would be more appropriate to follow up the patients without giving antiviral prophylaxis.


INTRODUCTION
Anti-tumor necrosis factor-alpha (TNF-α) and disease-modifying antirheumatic drugs (DMARDs) are used in the treatment of various rheumatic diseases, especially rheumatoid arthritis (RA) 1 .'Traditional DMARDs used in rheumatic treatment include methotrexate (MTX), hydroxychloroquine, sulfasalazine and leflunomide.DMARDs with potential hepatotoxic and immunosuppressive effects, such as MTX, can cause activation of the hepatitis B virus (HBV).In addition to these drugs, combining steroids with anti-TNF-α and other biologicals poses a risk for HBV activation 2 .TNF-α plays an important role in host defense.Patients treated with anti-TNF-α agents have increased susceptibility to infections.TNF-α is a cytokine that can suppress HBV replication and has an important role in the elimination of HBV by stimulating HBV-specific cytotoxic T-cell responses 3 .Prophylactic antiviral therapy has proven to be of significant benefit in preventing HBV reactivation in HBsAg positive patients treated with anti-TNF-α agents or DMARDs 4 .Therefore, it is recommended to initiate antiviral prophylaxis or treatment for chronic HBV infection in rheumatic patients receiving anti-TNF-α therapy or DMARDs 2 .
In this study, we aimed to evaluate the HBVr risk and physician awareness of HBVr in patients using anti-TNF-α due to inflammatory rheumatological disease.

Study population
The data of patients who received anti-TNF-α treatment at the rheumatology outpatient clinic of Recep Tayyip Erdoğan University Training and Research Hospital between June 2018 and June 2023 were retrospectively examined.

Data collection
Using our hospital's electronic record system, the patients' diagnoses, demographic characteristics, anti-TNF-α starting

Exclusion criteria
Patients who received anti-TNF-α treatment for less than 2 months, patients under 18 years of age, cancer patients, patients with insufficient viral marker data, patients without clinical follow-up and laboratory results, and those who were found to be positive for hepatitis C virus RNA were excluded from the study.

Definitions
HBsAg and/or anti-HBc tests were performed within 6 months before the start of treatment with anti-TNF-α drugs, HBV screening, and patients with HBsAg positivity detected for more than 6 months were defined as chronic hepatitis B patients.HBsAg negative/anti-HBc positive patients are defined as having recovered from HBV infection 5,6 .While monitoring patients, HBV reactivation was defined as a 10-fold increase in viral load from baseline negative to HBV DNA positivity and/or a change from baseline negative to HBsAg positivity [5][6][7] .Hepatitis was defined as an increase in the serum alanine aminotransferase (ALT) level of at least three times the upper limit of normal (45 U/L for serum ALT) 6 .HBV-related hepatitis was defined as clinical and biochemical evidence of hepatitis with an increase in HBV DNA 5 .

Serological and virological evaluation for hepatitis B virus infection
Hepatitis B virus serological markers, including HBsAg, anti-HBs, and anti-HBc levels, were evaluated by electrochemiluminescence immunoassay method using the Roche Cobas e6001 device (Roche Diagnostics, Mannheim, Germany).Serum HBV DNA levels were measured by Rotor-Gene Q (QIAGEN, Hilden, Germany) real-time polymerase chain reaction method (lower detection limit was 12 IU/mL).Routine biochemical parameters were tested using the Roche Hitachi Cobas 8000 Modular Analyzer system (Roch Diagnostics, Germany).

Statistical analysis
The SPSS Windows version 22 program was used in statistical tests.Continuous variables were evaluated for normal distribution with histogram, Q-Q graph, and Shapiro-Wilk or Kolmogorov-Smirnov test depending on the number of variables.Among continuous variables, those with normal distribution were presented as mean±standard deviation throughout the entire study, and independent variables t-test was used to compare the two groups.Other continuous variables were presented with median (minimum-maximum) values, and the non-parametric Mann-Whitney U test was used to compare the groups.Categorical variables were presented as frequency and percentage, and Pearson chi-square test or Fisher's exact probability test was used to compare the groups.Tests with a p-value of 0.05 or less within the 95% confidence interval were considered statistically significant.

RESULTS
A total of 448 patients were included in the study, of whom 240 (53.6%) patients were female and 208 (46.4%) were male.The average age of the patients was 48.02±14.64years, and the average age of women was significantly higher than that of men (p<0.001)(Table 1).
HBsAg was examined in 443 (98.9%) patients before treatment.While anti-HBc IgG was examined in 405 (90.4%) patients, it was not examined in 43 (9.6%) patients.Anti-HBc IgG test was positive in 69 (17%) patients.HBsAg (total 446-99.6%)test was performed in three patients who were not tested for HBsAg before the treatment, and an anti-HBc total (431-96.2%total) test was performed in 26 patients who were not tested for anti-HBc total.While the total number of HBsAg positive patients was 7 (1.6%), the number of HBsAg negative/anti-HBc total positive patients was 69 (16%).
A total of 24 patients received antiviral treatment.In addition, 11 patients received entecavir, 12 received tenofovir disoproxil fumarate (TDF), and 1 received lamivudine treatment.Cure O et al.
Antiviral treatment was started prophylactically in all HBsAg positive patients, 1 with entecavir and 6 with TDF.Antiviral treatment was started prophylactically in 17 (24.6%)patients, including entecavir in 10 patients, TDF in 6 patients, and lamivudine in 1 patient with HBsAg negative and anti-HBc total positive.

HBsAg negative/anti-HBc total positive patients
The average age of 69 patients with HBsAg negative/anti-HBc total positive was 54.33±13.07years and 45 of them (65.2%) were women.The average age of women was higher than men (p=0.016).The median follow-up period was 24 (6-60) months.

DISCUSSION
Hepatitis B infection is one of the most common infections worldwide.Chronic hepatitis B infection is an important cause of morbidity and mortality in society, leading to the development of hepatocellular cancer and cirrhosis.HBVr occurs with the reactivation of the patients' immune response against HBV.
In cases of immunosuppression from any cause, immune-mediated control of HBV replication is impaired and reactivation may subsequently occur.Anti-TNF-α inhibitors, steroids, and other immunosuppressive drugs used in rheumatological diseases may cause the functions of T and B lymphocytes to deteriorate, thus suppressing the immune response to HBV 8,9 .
In a study conducted by Lan et al., it was reported that 40% of chronic hepatitis B patients developed HBVr due to the use of anti-TNF-α, and 5% of them had a mortality risk 10 .In another study, the HBVr rate was found to be between 27 and 39% in HBsAg positive patients receiving anti-TNF-α.In the study conducted by Pérez Alvarez et al., HBVr was reported in 35 (39%) out of 87 HBsAg positive patients receiving anti-TNF-α and in 9 (5%) out of 168 HBsAg negative/anti-HBc positive patients.One of the HBsAg negative/anti-HBc positive patients died due to fulminant liver failure 11,12 .In a study, it was reported that in patients receiving anti-TNF-α therapy with an indication of autoimmune disease, 9 out of 23 patients (39%) who were HBsAg positive at the beginning of treatment developed HBVr, but none of the 178 HBsAg negative/ anti-HBc positive patients developed HBVr 7 .In our study, no patient developed HBVr, regardless of hepatitis serology and antiviral prophylaxis.
The Asian Pacific Association for the Study of the Liver and the American Association for the Study of Liver Diseases guidelines recommend prophylactic antiviral treatment during treatment and for up to 12 months after discontinuation of treatment in all HBsAg positive patients receiving immunosuppressive therapy, regardless of HBV DNA level.The European Association for the Study of Liver Diseases Study of the Liver recommends preemptive treatment during treatment and for up to 12 months after discontinuation of treatment in all HBsAg positive patients who are candidates for immunosuppression or chemotherapy, regardless of HBV DNA level.Regarding HBsAg negative/anti-HBc positive patients, all guidelines recommend that if the HBV DNA level is detectable, the patients should be treated as if they were HBsAg positive [13][14][15] .In our study, prophylactic antiviral treatment was started in all 7 HBsAg positive patients and in 17 (24.6%)HBsAg negative/ anti-HBc total positive patients, even though 10 of them had negative HBV DNA levels and 7 of them had not had HBV DNA levels checked.
Most reported cases of HBVr in HBsAg negative/anti-HBc positive patients occurred in patients receiving concomitant use of anti-TNF-α therapy and other immunosuppressive drugs 16,17 .In our study, although 32 (46.3%) of the negative/anti-HBc

Table 1 .
Demographic characteristics of the patients.
aT-test, SD: standard deviation.Statistically significant value is denoted in bold.

Table 2 .
Demographic characteristics of HBsAg negative/anti-HBc total positive patients.
aT-test, SD: standard deviation.Statistically significant value is denoted in bold.